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CS6250 COMPUTER NETWORK EXAM 2
ACTUAL EXAM 2026/2027 Complete
Questions and Answers Expert Verified Pass
Guaranteed - A+ Graded
SECTION 1: SOFTWARE-DEFINED NETWORKING
Q1: In an OpenFlow-based SDN network, a switch receives a packet for which it has no
matching flow table entry. Which of the following actions will occur?
A. The switch drops the packet immediately to prevent forwarding loops
B. The switch forwards the packet using traditional MAC learning
C. The switch encapsulates the packet and sends it to the controller
D. The switch floods the packet out all ports except the incoming port
Correct Answer: C
Rationale: In OpenFlow, when a packet does not match any flow table entry (table-miss), the
switch's default behavior is to send the packet to the controller for processing. Option C is
correct because the controller can then decide how to handle the packet and potentially install
new flow entries. Option A is incorrect because dropping is only one possible table-miss action,
not the default. Option B is incorrect because SDN decouples control and data planes; traditional
MAC learning occurs in the control plane, not autonomously on the switch. Option D describes
traditional Ethernet switch behavior, not OpenFlow SDN.
Q2: Which of the following is a primary advantage of Software-Defined Networking
(SDN)?
A. Increased complexity in network management
B. Centralized control of network traffic
C. Higher latency in packet forwarding
D. Limited flexibility in network configuration
Correct Answer: B
Rationale: SDN provides centralized control of network traffic through the separation of the
control plane from the data plane. This allows for more flexible and dynamic network
management.
Q3: What is the primary function of the control plane in an SDN architecture?
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A. Forwarding packets based on MAC addresses
B. Making decisions about where traffic should be sent
C. Encapsulating packets for transmission
D. Monitoring network performance
Correct Answer: B
Rationale: The control plane in SDN is responsible for making decisions about where traffic
should be sent. This is typically handled by a centralized controller.
Q4: Which protocol is commonly used in SDN to communicate between the control plane
and the data plane?
A. OSPF
B. BGP
C. OpenFlow
D. SNMP
Correct Answer: C
Rationale: OpenFlow is a communication protocol that enables the control plane to interact with
the data plane in an SDN environment.
Q5: What is the role of ONOS in SDN?
A. It is a type of SDN switch
B. It is an open-source SDN operating system
C. It is a protocol for routing packets
D. It is a tool for monitoring network performance
Correct Answer: B
Rationale: ONOS (Open Network Operating System) is an open-source SDN operating system
designed to manage and control network devices.
Q6: Which of the following is a key feature of OpenDaylight?
A. It is a proprietary SDN controller
B. It is an open-source platform for SDN
C. It is a protocol for routing packets
D. It is a tool for monitoring network performance
Correct Answer: B
Rationale: OpenDaylight is an open-source platform for SDN that provides a modular and
flexible architecture for network management.
Q7: In an SDN network, where is the control logic typically located?
, 3
A. On each individual switch
B. In a centralized controller
C. In the data plane
D. In the application layer
Correct Answer: B
Rationale: In SDN, the control logic is typically located in a centralized controller, which
manages the network and makes decisions about traffic flow.
Q8: What is the primary benefit of separating the control plane from the data plane in
SDN?
A. Increased network latency
B. Simplified network management
C. Reduced network security
D. Limited network flexibility
Correct Answer: B
Rationale: Separating the control plane from the data plane simplifies network management by
centralizing control and allowing for more dynamic and flexible network configurations.
Q9: Which of the following is a disadvantage of traditional networking compared to SDN?
A. Centralized control
B. Dynamic configuration
C. Complex management
D. Low latency
Correct Answer: C
Rationale: Traditional networking often involves complex management due to the distributed
nature of control logic. SDN simplifies this by centralizing control.
Q10: What is the primary function of the data plane in an SDN architecture?
A. Making decisions about where traffic should be sent
B. Forwarding packets based on rules set by the control plane
C. Encapsulating packets for transmission
D. Monitoring network performance
Correct Answer: B
Rationale: The data plane in SDN is responsible for forwarding packets based on rules set by the
control plane.
Q11: Which of the following is a key feature of SDN controllers?
CS6250 COMPUTER NETWORK EXAM 2
ACTUAL EXAM 2026/2027 Complete
Questions and Answers Expert Verified Pass
Guaranteed - A+ Graded
SECTION 1: SOFTWARE-DEFINED NETWORKING
Q1: In an OpenFlow-based SDN network, a switch receives a packet for which it has no
matching flow table entry. Which of the following actions will occur?
A. The switch drops the packet immediately to prevent forwarding loops
B. The switch forwards the packet using traditional MAC learning
C. The switch encapsulates the packet and sends it to the controller
D. The switch floods the packet out all ports except the incoming port
Correct Answer: C
Rationale: In OpenFlow, when a packet does not match any flow table entry (table-miss), the
switch's default behavior is to send the packet to the controller for processing. Option C is
correct because the controller can then decide how to handle the packet and potentially install
new flow entries. Option A is incorrect because dropping is only one possible table-miss action,
not the default. Option B is incorrect because SDN decouples control and data planes; traditional
MAC learning occurs in the control plane, not autonomously on the switch. Option D describes
traditional Ethernet switch behavior, not OpenFlow SDN.
Q2: Which of the following is a primary advantage of Software-Defined Networking
(SDN)?
A. Increased complexity in network management
B. Centralized control of network traffic
C. Higher latency in packet forwarding
D. Limited flexibility in network configuration
Correct Answer: B
Rationale: SDN provides centralized control of network traffic through the separation of the
control plane from the data plane. This allows for more flexible and dynamic network
management.
Q3: What is the primary function of the control plane in an SDN architecture?
,2
A. Forwarding packets based on MAC addresses
B. Making decisions about where traffic should be sent
C. Encapsulating packets for transmission
D. Monitoring network performance
Correct Answer: B
Rationale: The control plane in SDN is responsible for making decisions about where traffic
should be sent. This is typically handled by a centralized controller.
Q4: Which protocol is commonly used in SDN to communicate between the control plane
and the data plane?
A. OSPF
B. BGP
C. OpenFlow
D. SNMP
Correct Answer: C
Rationale: OpenFlow is a communication protocol that enables the control plane to interact with
the data plane in an SDN environment.
Q5: What is the role of ONOS in SDN?
A. It is a type of SDN switch
B. It is an open-source SDN operating system
C. It is a protocol for routing packets
D. It is a tool for monitoring network performance
Correct Answer: B
Rationale: ONOS (Open Network Operating System) is an open-source SDN operating system
designed to manage and control network devices.
Q6: Which of the following is a key feature of OpenDaylight?
A. It is a proprietary SDN controller
B. It is an open-source platform for SDN
C. It is a protocol for routing packets
D. It is a tool for monitoring network performance
Correct Answer: B
Rationale: OpenDaylight is an open-source platform for SDN that provides a modular and
flexible architecture for network management.
Q7: In an SDN network, where is the control logic typically located?
, 3
A. On each individual switch
B. In a centralized controller
C. In the data plane
D. In the application layer
Correct Answer: B
Rationale: In SDN, the control logic is typically located in a centralized controller, which
manages the network and makes decisions about traffic flow.
Q8: What is the primary benefit of separating the control plane from the data plane in
SDN?
A. Increased network latency
B. Simplified network management
C. Reduced network security
D. Limited network flexibility
Correct Answer: B
Rationale: Separating the control plane from the data plane simplifies network management by
centralizing control and allowing for more dynamic and flexible network configurations.
Q9: Which of the following is a disadvantage of traditional networking compared to SDN?
A. Centralized control
B. Dynamic configuration
C. Complex management
D. Low latency
Correct Answer: C
Rationale: Traditional networking often involves complex management due to the distributed
nature of control logic. SDN simplifies this by centralizing control.
Q10: What is the primary function of the data plane in an SDN architecture?
A. Making decisions about where traffic should be sent
B. Forwarding packets based on rules set by the control plane
C. Encapsulating packets for transmission
D. Monitoring network performance
Correct Answer: B
Rationale: The data plane in SDN is responsible for forwarding packets based on rules set by the
control plane.
Q11: Which of the following is a key feature of SDN controllers?
